Method and apparatus for producing a high-velocity particle stream

Abstract

A method and apparatus for producing a high-velocity particle stream at low cost through multi-staged acceleration using different media in each stage, the particles are accelerated to a subsonic velocity (with respect to the velocity of sound in air) using one or more jets of gas at low cost, then further accelerated to a higher velocity using jets of water. Additionally, to enhance particle acceleration, a vortex motion is created, and the particles introduced into the fluid having vortex motion, thereby enhancing the delivery of particles to the target.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:  
     
       1. A method for producing a stream of particles moving at high velocity in a chamber, having an internal radius comprising the steps of: 
       (i) accelerating said particles to a subsonic velocity using at least one jet of gas; thereafter,  
       (ii) accelerating said particles to a higher velocity using at least one jet of liquid by contacting said stream at an oblique angle with at least one jet of ultra-high pressure water within the chamber.  
     
     
       2. A method for producing a stream of particles moving at high velocity in a chamber, having an internal radius comprising the steps of: 
       (i) accelerating said particles to a subsonic velocity using at least one jet of gas; thereafter;  
       (ii) accelerating said particles to a higher velocity using at least one jet of liquid by contacting said stream at an oblique angle with at least one jet of ultra-high pressure water within the chamber; and  
       (iii) inducing radial motion to said particles by the downstream injection of at least one jet of fluid.  
     
     
       3. The method of claim  2 , comprising the additional step of: 
       amplifying said radial motion to said particles by narrowing the internal radius of the chamber.  
     
     
       4. The method of claim  1 , comprising the additional step of: 
       inducing radial motion to said particles by narrowing the internal radius of the chamber.  
     
     
       5. The method of claim  1 , comprising the additional step of: 
       increasing the concentration of particles having a higher density than their surrounding fluid, in a high-velocity fluid stream further comprising the steps of:  
       (i) introducing said particles into a fluid stream having swirling flow; thereafter,  
       (ii) contacting said particles with a high-velocity fluid stream.  
     
     
       6. The method of claim  5 , comprising the additional step of: 
       amplifying said swirling flow into said stream by using a variable-radius chamber.  
     
     
       7. A method for producing a stream of particles moving at high velocity in a chamber, comprising the steps of: 
       (i) accelerating particles to subsonic velocity using at least one jet of gas; thereafter,  
       (ii) accelerating said particles to a higher velocity using at least one jet of liquid by contacting said stream at an oblique angle with at least one jet of ultra-high pressure water within the chamber; and  
       (iii) inducing radial motion to said particles by the introduction of at least one jet of fluid.  
     
     
       8. The method of claim  7  wherein said radial motion is induced by the upstream injection of at least one jet of fluid. 
     
     
       9. The method of claim  7  wherein said radial motion is induced by the downstream injection of at least one jet of fluid. 
     
     
       10. The method of claim  7  wherein said introduction of at least one jet of fluid occurs by injection of pressurized fluid. 
     
     
       11. The method of claim  7  wherein said introduction of at least one jet of fluid occurs by passive aspiration of fluid. 
     
     
       12. The method of claim  7  wherein said fluid is air. 
     
     
       13. A method for producing a stream of particles moving at high velocity in a chamber, comprising the steps of: 
       (i) accelerating particles to subsonic velocity using at least one jet of gas; thereafter,  
       (ii) accelerating said particles to a higher velocity using at least one jet of liquid by contacting said stream with at least one jet of ultra-high pressure water within the chamber; and  
       (iii) inducing radial motion to said particles by the introduction of at least one jet of fluid.  
     
     
       14. A method for producing a stream of particles moving at high velocity in a chamber, comprising the steps of: 
       (i) accelerating particles to subsonic velocity using at least one jet of gas; thereafter,  
       (ii) accelerating said particles to a higher velocity using at least one jet of liquid by contacting said stream at an oblique angle with at least one jet of ultra-high pressure water within the chamber; thereafter,  
       (iii) inducing radial motion to said particles by manipulating the internal configuration of said chamber.  
     
     
       15. The method of claim  14  wherein said radial motion is induced by a plurality of vanes placed in an interior wall of said chamber. 
     
     
       16. The method of claim  14  wherein said radial motion is induced by a plurality of grooves placed in an interior wall of said chamber. 
     
     
       17. The method of claim  14  wherein said radial motion is induced by varying the internal geometry of said chamber. 
     
     
       18. The method of claim  14 , comprising the additional step of: 
       amplifying said radial motion by narrowing the internal radius of the chamber.  
     
     
       19. The method of claim  14 , comprising the additional step of: 
       inducing spreading of said stream by downstream widening of the internal radius of the chamber.  
     
     
       20. The method of claim  14  wherein said abrasive particle stream is accelerated to a velocity of greater than about 600 ft/sec. 
     
     
       21. A method for increasing the concentration of particles having a higher density than their surrounding fluid, in a high-velocity fluid stream, comprising the steps of: 
       (i) introducing said particles into a fluid stream having radial flow; and  
       (ii) contacting said particles with an ultra-high pressure liquid stream.  
     
     
       22. The method of claim  21 , comprising the additional step of passing said particles through a chamber of decreasing radius. 
     
     
       23. The method of claim  21 , comprising the additional step of passing said particles through a chamber of decreasing radius, and thereafter passing said particles through a chamber of increasing radius. 
     
     
       24. A method for generating an ultra-high pressure fluid-abrasive stream, comprising: 
       providing a pressurized stream of abrasive particles and air to a nozzle inlet;  
       accelerating the pressurized stream of abrasive particles to a first velocity, the pressurized stream of abrasive particles entering a mixing chamber;  
       introducing an ultra-high pressure liquid jet into the mixing chamber, the ultra-high pressure liquid jet contacting and accelerating the pressurized stream of abrasive particles to a second velocity that is higher than the first velocity to generate an ultra-high pressure fluid-abrasive stream; and  
       discharging the ultra-high pressure fluid-abrasive stream through an exit orifice.  
     
     
       25. The method of claim  24  further comprising: 
       selectively allowing and preventing the flow of abrasive particles through the nozzle inlet.  
     
     
       26. The method of claim  24  further comprising: 
       selectively allowing and preventing the flow of the ultra-high pressure liquid jet upstream of the mixing chamber.